1. Field of the Invention
The invention relates to an illuminating device, more particularly to an organic light emitting diode illuminating device.
2. Description of the Related Art
Referring to FIG. 1, Taiwanese Patent No. I307559 discloses a conventional organic light emitting diode (abbreviated as OLED hereinafter) illuminating device 1, which includes a substrate 11, a bottom electrode layer 12, an organic light emitting structure 13 disposed on the bottom electrode layer 12, a top electrode layer 14 disposed on the organic light emitting structure 13, and a packaging cover 15.
The bottom electrode layer 12 is formed on a top surface of the substrate 11 and has an inner electrode zone 122 and an outer electrode zone 121 that is electrically coupled to the inner electrode zone 121 and that is exposed from the organic light emitting structure 13. The top electrode layer 14 has an inner electrode zone 142 that covers the organic light emitting structure 13, and an outer electrode zone 141 that is electrically coupled to the inner electrode zone 142 of the top electrode layer 14, that is formed on the top surface of the substrate 11, and that is spaced apart from the bottom electrode layer 12. The packaging cover 15 partially covers the outer electrode zones 121, 141 of the top and bottom electrode layers 12, 14.
People who have ordinary skill in the art would appreciate that the top and bottom electrode layers 12, 14 are usually made of a metallic material having high electrical conductivity. Although the packaging cover 15 of the conventional OLED illuminating device 1 can prevent the inner electrode zones 122, 142 of the top and bottom electrode layers 12, 14 from being exposed to the exterior environment, the outer electrode zones 121, 141 of the top and bottom electrode layers 12, 14, which are partially exposed to the exterior environment, are highly susceptible to damage caused by reaction with atmospheric components such as oxygen and water, thereby adversely affecting electrical property thereof. Moreover, when a functional testing is performed, a probe which is in contact with the outer electrode zones 121, 141 of the top and bottom electrode layers 12, 14 may cause damage thereto and adversely affect the electrical property thereof.
U.S. Pat. No. 7,026,660 B2 discloses a conventional OLED device provided with a polyimide layer to encapsulate contact conductors, but bond pads thereof are exposed to the exterior environment and may still suffer from damage caused by detrimental reaction with atmospheric constituents such as oxygen and water.
Therefore, there is a need in the art to improve the structure of the OLED illuminating device so as to prolong the service life of the OLED illuminating device.